1. Field of the Invention
The present invention relates to a wavelength-converted light generating apparatus and generating method for generating and outputting converted light resulting from wavelength conversion of excitation light made incident on a wavelength conversion element.
2. Related Background Art
As an optical element that performs wavelength conversion on infrared light as incident light and outputs visible light of a shorter wavelength than the infrared light as output light, there is conventionally known an element with which visible light energy, such as that of illumination light, is stored in a substance in advance and the stored energy is output as visible light luminescence by stimulation of the substance by incidence of infrared light (see Non-Patent Document 1, IR Sensor Card: Model #5842, manufactured by New Focus Inc.).
As an optical element that likewise performs wavelength conversion of infrared light to visible light, there is known an element that makes use of second harmonic generation or other nonlinear optical phenomenon to shorten a wavelength of infrared light and wavelength-convert the infrared light to visible light (see Non-Patent Document 2).
Patent Document 1: Japanese Patent Application Laid-Open No. 2007-95859
Patent Document 2: Japanese Patent Application Laid-Open No. 2004-235574
Patent Document 3: Japanese Patent Application Laid-Open No. 2003-13236
Patent Document 4: Japanese Patent Application Laid-Open No. 2004-107744
Non-Patent Document 1: B. O'Brien, “Development of Infra-Red Sensitive Phosphors,” J. Opt. Soc. Am., Vol. 36, No. 7 (1946) pp. 369-371
Non-Patent Document 2: P. A. Franken et al., “Generation of Optical Harmonics,” Phys. Rev. Lett., Vol. 7, No. 4 (1961) pp. 118-119